I am looking for some input from yall that have this set up on there rubi/foreman 2001ish. I am running a hmf swamp series xl exhaust with a uni filter and i have my jet at 170 my stock was 158. had my stock in ran fine but as we all know you gotta jet when doing add ons to catch the fuel with the intake of new air. didnt smoke on my stock jet but now im puffing black when i bump the trottle from idle with the 170. hmf sudjested this being the jet for the pipe to bike but i thinking im to rich. Who has this set up and what are you running? thanks for the help!

Has anyone installed a fcr 37mm on a 400ex?? Got a friend that has had a fcr 37mm given to him, and he is determined to install it on his 400. I’m up in the air about the whole mod in general at this point. Being that it’s downsizing as far as airflow(CFM) is concerned. I know it’s only 1mm smaller than stock so another part of me says he will gain the FCR’s throttle response in return. So where do we start with the main and pilot?? 400ex mods are: Big gun ES full exhaust, 11:1 stock bore, stage 2 HC, no lid/W K&N, AMR stage 3 CDI and stock valves and no port work. 175 – 180????? 40 – 45???????

I bought a 400ex and replaced the main jet and pilot jet already. The quad came with a slip on exhaust and never ran right. When i push the throttle i can only push the throttle half way then it bogs down and shuts off. I had this issue with another quad and put bigger jets in. I already put a Keihin Hex Main Jet 160 and a 42 pilot jet do you guys think i need to go bigger? I have a K&n air filter on it and the top of the air box has three 3/4th inch holes in it from the previous owner.

I bought a used DMC alien full exhaust. It was from a 2003 trx250ex. I have a 2007 model. My own muffler had two bracket for mounting. This muffler has one towards the front of bike. Question… should i have a experienced welder friend weld up another out of aluminium or will one be enough? I dont want to use a strap. Ruins the clean look.

I bought a used DMC alien full exhaust. It was from a 2003 trx250ex. I have a 2007 model. My own muffler had two bracket for mounting. This muffler has one towards the front of bike. Question… should i have a experienced welder friend weld up another out of aluminium or will one be enough? I dont want to use a strap. Ruins the clean look.

I plan on take off the head and clean up the combustion chamber and intake and exhaust ports. Do i need to replace head gasket or can i reuse? Any other gasket id need to replace? Also i cant find just a head gasket, they’re all upper head gasket kits.

So as some of you may remember my 02 300ex build which can be google searched under that^ exact name.

But anyways here we go again, but this time I’m going for more power on the engine with a namura 330CC big bore kit, I already got a mid to high range ported and polished head, and I just finally ordered the 330 kit.

I started this thread to get some help, I have a manual, but what kinda things can I run into here?

It’s a 02, could I still run into case clearance issues, and I’m using the stock cam, and arms, but I got kibble white performance springs on the new head.

What kind of power increase am I looking at, and can someone point me in the right direction to start with main jet sizes? My current is 165 main, 42 slow.

Motor Mods:
FMF full exhaust
400ex carb
Uni filter with 8 half inch holes drilled in box.

Thanks,

Pics to fallow,

Dj

I just started using that sea foam with some noticeable results. Smoother engine sound and feel mostly. But my rancher 350 seems a bit sluggish when pushed in the high gears. I’m getting about 45mph max. From what I’ve read, that’s a bit slow. It is an all time 4×4 so maybe that’s all I can get? Just ordered a new air filter. Not expecting much but I’m sure it’s overdue anyway.

I have a 2005 trx450r. With a 12:1 compression piston full HMF competition series exhaust and a K and N air filter with outwear but no air box lid. What jets and needle adjustment do I need. I love in clarion county pa

Hello all,

I’m going to be buying one of the package deals from ebay with an HMF Exhaust, Optimizer, and Uni Filter for my 2007 Rincon. My question is, should I go with the standard Competition Series, or the Penland Series?

HMF claims the the Competition gives power throughout the RPM range, and that the Penland gives more low-end power.

I am not worried about the sound level, just want it to sound good and get the best bang for my buck. They are almost the same price. I mostly trail ride my Rincon and the majority of the time my girlfriend is on with me. I’m sure an increase in low-end would be most helpful, but more power all around would probably be great too.

Thanks, looking for any input on the subject and I am open to suggestions

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